Like uprobe_syscall_args; keep things consistent.
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
arch/x86/kernel/uprobes.c | 33 ++++++++++++++++++++-------------
1 file changed, 20 insertions(+), 13 deletions(-)
--- a/arch/x86/kernel/uprobes.c
+++ b/arch/x86/kernel/uprobes.c
@@ -311,6 +311,12 @@ static int uprobe_init_insn(struct arch_
#ifdef CONFIG_X86_64
+struct uretprobe_syscall_args {
+ unsigned long r11;
+ unsigned long cx;
+ unsigned long ax;
+};
+
asm (
".pushsection .rodata\n"
".global uretprobe_trampoline_entry\n"
@@ -324,8 +330,8 @@ asm (
"uretprobe_syscall_check:\n"
"popq %r11\n"
"popq %rcx\n"
-
- /* The uretprobe syscall replaces stored %rax value with final
+ /*
+ * The uretprobe syscall replaces stored %rax value with final
* return address, so we don't restore %rax in here and just
* call ret.
*/
@@ -366,7 +372,8 @@ static unsigned long trampoline_check_ip
SYSCALL_DEFINE0(uretprobe)
{
struct pt_regs *regs = task_pt_regs(current);
- unsigned long err, ip, sp, r11_cx_ax[3], tramp;
+ struct uretprobe_syscall_args args;
+ unsigned long err, ip, sp, tramp;
/* If there's no trampoline, we are called from wrong place. */
tramp = uprobe_get_trampoline_vaddr();
@@ -377,15 +384,15 @@ SYSCALL_DEFINE0(uretprobe)
if (unlikely(regs->ip != trampoline_check_ip(tramp)))
goto sigill;
- err = copy_from_user(r11_cx_ax, (void __user *)regs->sp, sizeof(r11_cx_ax));
+ err = copy_from_user(&args, (void __user *)regs->sp, sizeof(args));
if (err)
goto sigill;
/* expose the "right" values of r11/cx/ax/sp to uprobe_consumer/s */
- regs->r11 = r11_cx_ax[0];
- regs->cx = r11_cx_ax[1];
- regs->ax = r11_cx_ax[2];
- regs->sp += sizeof(r11_cx_ax);
+ regs->r11 = args.r11;
+ regs->cx = args.cx;
+ regs->ax = args.ax;
+ regs->sp += sizeof(args);
regs->orig_ax = -1;
ip = regs->ip;
@@ -401,21 +408,21 @@ SYSCALL_DEFINE0(uretprobe)
*/
if (regs->sp != sp || shstk_is_enabled())
return regs->ax;
- regs->sp -= sizeof(r11_cx_ax);
+ regs->sp -= sizeof(args);
/* for the case uprobe_consumer has changed r11/cx */
- r11_cx_ax[0] = regs->r11;
- r11_cx_ax[1] = regs->cx;
+ args.r11 = regs->r11;
+ args.cx = regs->cx;
/*
* ax register is passed through as return value, so we can use
* its space on stack for ip value and jump to it through the
* trampoline's ret instruction
*/
- r11_cx_ax[2] = regs->ip;
+ args.ax = regs->ip;
regs->ip = ip;
- err = copy_to_user((void __user *)regs->sp, r11_cx_ax, sizeof(r11_cx_ax));
+ err = copy_to_user((void __user *)regs->sp, &args, sizeof(args));
if (err)
goto sigill;
